Public bug reported: [Impact]
In both 5.4 and 5.8 kernel, there are two patches in PCI to workaround an issue with GPU and Infiniband at the time. Those two patches are no longer necessary in today's Azure environment. Those two patches introduces bugs to the latest Azure HPC VM SKU. 4.15 kernel is not affected. Microsoft has regression tested and verified that the following two patches can be dropped or reverted in 5.4 and 5.8. 5.4 kernel: Patch 1: Revert "PCI: hv: Make sure the bus domain is really unique" https://git.launchpad.net/~canonical-kernel/ubuntu/+source/linux-azure/+git/bionic/commit/drivers/pci/controller/pci-hyperv.c?h=azure-5.4&id=faf2750396d60001046333bd46eee757bb4cac7b Patch 2: UBUNTU: SAUCE: pci-hyperv: Use only 16 bit integer for PCI domain https://git.launchpad.net/~canonical-kernel/ubuntu/+source/linux-azure/+git/bionic/commit/drivers/pci/controller/pci-hyperv.c?h=azure-5.4&id=04ac3e06ab708131c1c18cb7db10ca5dd6feedce 5.8 kernel: Patch 1: Revert "PCI: hv: Make sure the bus domain is really unique" https://git.launchpad.net/~canonical-kernel/ubuntu/+source/linux-azure/+git/groovy/commit/drivers/pci/controller/pci-hyperv.c?h=Ubuntu-azure-5.8.0-1016.17&id=7c85402203e26d4d0474f69b99b5a06ffb765630 Patch 2: UBUNTU: SAUCE: pci-hyperv: Use only 16 bit integer for PCI domain https://git.launchpad.net/~canonical-kernel/ubuntu/+source/linux-azure/+git/groovy/commit/drivers/pci/controller/pci-hyperv.c?h=Ubuntu-azure-5.8.0-1016.17&id=b72f314d15ab0ad7b80b761d8167962300c1bd35 [Test Case] As per #1816106, instances with multiple GPUs should still be able to see all of them. [Where problems could occur] Issues or oops in instances types with multiple GPUs. ** Affects: linux (Ubuntu) Importance: Undecided Assignee: Marcelo Cerri (mhcerri) Status: New ** Affects: linux (Ubuntu Focal) Importance: Undecided Status: In Progress ** Affects: linux (Ubuntu Groovy) Importance: Undecided Status: In Progress ** Also affects: linux (Ubuntu Groovy) Importance: Undecided Status: New ** Also affects: linux (Ubuntu Focal) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Focal) Status: New => In Progress ** Changed in: linux (Ubuntu Groovy) Status: New => In Progress -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1911205 Title: Revert or drop obsolete patches for PCI To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1911205/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
